When instructed, open your envelope and verify that your group has 9 puzzle pieces: 1
carbon (C), 1 chlorine (Cl), 1 oxygen (O), 1 phosphorus (P), 2 fluorine (F), and 3 hydrogen (H).
The puzzle pieces represent Lewis dot symbols (the dots represent the valence electrons around
a neutral atom of that element), and allow you to pair up electrons and create molecules that are
covalently bonded. Like last week, look for patterns when completing these.
1. Use the puzzle pieces to construct the molecules given below (a-e). Then draw the Lewis
dot structure for each molecule, leaving off the outline of each puzzle piece.
a. PH3
b. HOCl
c. F2
d. CH3Cl
e. your choice
2. Use the puzzle pieces to create the molecules given below (even though you don’t have
all the necessary puzzle pieces, you have some elements in the same group). For each
molecule, draw the Lewis dot structure and write the molecular formula.
a. Use one S atom and as many H atoms as you need.
b. Use one Si atom and as many F atoms as you need.
c. Use two O atoms and as many H atoms as you need.
3. Use the puzzle pieces to construct a molecule with the molecular formula C2H6. Draw the
Lewis dot structure and the structural formula.
4. Looking back at the previous problems, did you notice any patterns?
a. Of the molecules that you created, was there a center to the molecule? Was there
anything special about the central atom?
b. When you look at the valence electrons that surround each atom, are the numbers
of electrons random or is there a pattern?